More of California experiencing most severe drought conditions

As California enters summer with a below-normal mountain snowpack to feed its streams and reservoirs, the portion of the parched state experiencing exceptionally severe drought conditions is growing, experts said.

The most populous U.S. state is in the third year of a crippling drought that has forced ranchers to sell cattle for lack of grazing land, and farmers to let an estimated 400,000 acres normally devoted to crops go fallow.

The U.S. Department of Agriculture said Thursday that while all of the state remains in a severe drought, the portion of the state in what is considered an "exceptional drought" increased in the past week from about 25 percent to about 33 percent.

Part of the increase was due to a re-evaluation of the impact of dry conditions on the northern part of the state, Michael Anderson, California's state climatologist, said Friday.

But he said that drought experts expect conditions to worsen as the summer continues - and not just because summers in California are typically hot and dry.

"Usually about this time of year we kind of settle into a pattern where it stabilizes and we don't expect things to change," Anderson said. "But in this case with the severity of the drought we expect to see more impacts come up as the summer progresses."

Part of the reason, Anderson said, is that the state started the warmer season with a snowpack in the Sierra Nevada that was much smaller than usual, meaning there was less snow to melt and run down into lakes and streams.

Throughout the summer, he predicted, more of the state would fall into the worst category of drought.